Quote:
Originally Posted by Daox
Interesting, they're closing the intake valve early on the intake stroke vs leaving it open longer on the compression stroke. It seems like the Atkinson cycle would still be superior for efficiency purposes as it would reduce pumping losses more than the Budack cycle. However, there isn't air/fuel going back out the intake valve which is a nice thing. Overall I bet the differences between the two are negligible. Therefore it probably comes down to whatever is easier/cheaper to manufacture.
|
I'm thinking the opposite is true - with the Atkinson cycle, the piston has to do the work of both pulling the air into, and pushing it back out of the cylinder, which to my logic takes more energy.
Also, because you end up with a piston creating lower pressure in the cylinder with the remainder of the downstroke, you're depressurizing the air and may actually be pulling heat out of the cylinder walls, rather than losing it into them, which would be a net thermodynamic gain.